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21.
M. Kaneko M. Higashimori R. Takenaka A. Namiki M. Ishikawa 《Mechatronics, IEEE/ASME Transactions on》2003,8(1):37-44
This paper discusses the capturing robot with the maximum acceleration of 100 G in design specification. We aim find the combination of the arm with a mass of 0.1 kg and the spring capable of producing the initial compressed force of 100 N, in order to achieve the 100 G. To reduce the total capturing time, we propose an arm/gripper coupling mechanism where the spring energy initially accumulated in the arm is transferred to the kinetic energy of the arm and continuously to the kinetic energy for closing the gripper at the capturing point without any time lag. The experimental results show the maximum acceleration of 91 G and the capturing time of 25 ms were achieved. Experiments on capturing a dropping ball were also executed with the assistance of the 1 ms-vision. 相似文献
22.
The surface tension of liquid palladium and the contact angle between liquid palladium and sapphire have been measured at 1833 K as a function of oxygen pressure by the sessile drop method. Oxygen acted as a surface-active element on the surface of liquid palladium and at the interface between liquid palladium and sapphire, resulting in the decrease of the surface tension and the contact angle. The work of adhesion calculated from their values increased with increasing oxygen pressure, and had a constant value above 400 Pa. The maximum excess concentration of oxygen was estimated to be 7.3×10–6 mol m–2 for the surface and 6.9×10–6 mol m–2 for the interface. 相似文献
23.
M Fujimoto H Kanzaki H Nakayama T Higuchi H Hatayama M Iwai Y Kaneko T Mori J Fujita 《Canadian Metallurgical Quarterly》1996,137(3):1096-1101
Differentiation of endometrial stromal cells (decidualization) is essential for embryo implantation and maintenance of pregnancy. By sequential complementary DNA subtractive hybridization, one of the messenger RNAs (mRNA) induced by progesterone in human endometrial stromal cells decidualized in vitro was identified as that of a tissue transglutaminase type II (TGase). TGase mRNA was induced within 6 h after the addition of progesterone to the culture, and the effect was dose dependent. Both the TGase inhibitor monodansylcadaverine and oligodeoxynucleotide complementary to the TGase mRNA inhibited the decidualization, as assessed by PRL production and morphological transformation. Expression of TGase mRNA in human decidua and endometria exposed to high levels of progesterone in vivo was demonstrated by Northern blotting and in situ hybridization. These data suggest that TGase is necessary for the decidualization of human endometrial stromal cells and that clarification of the mechanism of action of TGase will facilitate further insight into the diagnosis and treatment of infertility. 相似文献
24.
Serum rheumatoid factor (RF) level and peritoneal and splenic CD5+B (B-1) cells in mice were examined after intraperitoneal administration of purified lipopoly-saccharides (LPS) from oral periodontopathic bacteria; Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum and Capnocytophaga ochracea. F. nucleatum and C. ochracea LPS induced higher levels of serum IgM- and IgG-RF, while P. gingivalis LPS showed the least induction. In addition, wet weights of spleen and serum IgM and IgG concentration were markedly increased in F. nucleatum LPS injected group. On the other hand, the proportion of CD5+ B cells to lymphocytes in the peritoneal cavity and spleen did not increase. The reason for this was not clear but conventional B cells (CD5- B cells) might increase more rapidly with splenic enlargement than CD5+ B cells. These results suggested that RF induced by bacterial LPS may modulate immune responses against bacteria and plays an important role for defence and destruction of periodontal tissue. 相似文献
25.
26.
Teruya Tanaka Junichi. H. Kaneko Yoshimi Kasugai Masaki Katagiri Hiroshi Takeuchi Takeo Nishitani Toshiyuki Iida 《Diamond and Related Materials》2005,14(11-12):2031
Radiation tolerance of a type IIa synthetic diamond detector was examined from irradiation of mono-energetic 14 MeV neutrons. Measurements of I–V (current–voltage) characteristics and energy spectrum for 5.486 MeV alpha particles were performed after neutron irradiation. In the I–V characteristics measurement, enhancement of rectification was observed after neutron irradiation of up to 2.0 × 1012 n/cm2. Concurrently with the enhancement of rectification, significant decrease in signal amplitude was observed in energy spectrum measurement for alpha particles. It is considered that these changes were due to increase in the concentration of defects acting as shallow energy levels in the forbidden band. For neutron irradiation of higher than 1.6 × 1013 n/cm2, weakening of the rectification characteristics and recovery of the signal amplitude were observed. These changes imply that deep energy levels, which were also considered to be introduced by defects, were dominant and weakened the effects of the shallow energy levels. Increase in the concentration of the deep trapping levels resulted in gradual decrease of the signal amplitude and degradation in the energy resolution. The peak for the alpha particles was obtained up to 5.5 × 1013 n/cm2. 相似文献
27.
Athermal silica-based arrayed-waveguide grating multiplexer 总被引:4,自引:0,他引:4
Inoue Y. Kaneko A. Hanawa F. Takahashi H. Hattori K. Sumida S. 《Electronics letters》1997,33(23):1945-1947
A temperature dependent channel wavelength shift in a silica-based arrayed-waveguide grating multiplexer is successfully suppressed from 0.95 to 0.05 nm in the 0-85°C temperature range, which means that it can be used in practical WDM systems without the need for temperature control 相似文献
28.
Kaneko M. Aratani K. Fukumoto A. Miyaoka S. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1994,82(4):544-553
IRISTER (IRIS Thermal Eclipse Reading) is a remarkable technique for achieving superresolution in optical disks. Two applications of IRISTER are Magnetically induced SuperResolution (MSR) and Premastered optical disk by SuperResolution (PSR). Magnetically induced SuperResolution (MSR) has been realized in magneto-optical disks using exchange-coupled magnetic multilayer films. Two new detection methods have been developed. In the front aperture detection (FAD) method, the heated area in the light spot works as an optical mask so that the signal is read out only from the remaining crescent-shaped area in the spot. In the rear aperture detection (RAD) method, the signal is read out only from the heated area. The cutoff spatial frequency for both types of detection is more than two times higher than that in conventional detection. A high C/N of 42 dB is obtained in the MSR disks by both methods for a mark length of 0.3 μm, which is much shorter than the optical limit. Premastered optical disk by SuperResolution (PSR) has been realized in read-only optical disks using phase-change materials. In the front aperture detection (FAD) method for PSR, the prerecorded signal is read out only from the high reflective crescent-shaped area in the light spot, because the reflectance of the heated area is too low. A C/N of 51 dB for a mark length of 0.3 μm has been obtained for the PSR disk 相似文献
29.
The hemostatic effect of aprotinin in pediatric cardiac surgery is controversial. This study demonstrated the usefulness of aprotinin in cases undergoing additional surgery. In a retrospective study, three groups of children were investigated. In group I (n = 10), no aprotinin or Cell saver was used (control). In group II (n = 12), Cell saver was used intraoperatively. In group III (n = 14), aprotinin 30,000 KIU/kg was added to the prime of cardiopulmonary bypass, and another 10,000 KIU/kg was given every hour during extracorporeal circulation. Both blood loss and use of homologous blood during operation were significantly (p < 0.01) reduced in group III compared to those in the other two groups. In group III, blood loss both 12 and 48 hours postoperatively were one-third less than those in group I (no significant difference). The use of homologous blood 48 hours postoperatively was significantly reduced in group III compared to that in group I (p < 0.01) or group II (p < 0.05). We conclude that aprotinin administration during cardiopulmonary bypass reduced blood loss and homologous blood requirements both operatively and postoperatively when pediatric cardiac surgery must be redone. 相似文献
30.
On-Line Shape recognition with incremental training using binary synaptic weights algorithm 总被引:2,自引:0,他引:2
Recognition of hand drawn shapes is beneficial in drawing packages and automated sketch entry in handheld computers. In this paper, we propose a new approach to on-line geometric shape recognition with incremental training function, which utilizes a heuristic function to reduce noise and a neural network for classification and on-line training. Instead of recognizing segments of a drawing and then performing syntactical analysis to match with a predefined shape, which is weak in terms of generalization and dealing with noise, we examine the shape as a whole. The main concept of the recognition method is derived from the fact that internal angles are very important in the perceived shape of outlines. Our application's aim is to recognize elliptic, rectangular, and triangular shapes in a way similar to human cognition of these shapes. Human beings recognize such basic shapes regardless of the variations in size, noise on the shape border, rotation and in the case of triangles, regardless of the type of the triangle. The key concept is that the neural network learns the relationships between the internal angles of a shape and its classification, therefore only a few training samples which represent the class of the shape are sufficient. Fast meremental training, which is performed on-line, is accomplished by the use of the Binary Synaptic Weights algorithm, a one pass, feedforward neural network training algorithm. Incremental training offers the advantage of adjusting the recognition capability of the system to the user's drawings. the results are very successful, such that the neural network correctly classified shapes that did not have any resemblance to the shapes in the initial training set. 相似文献